Impact-damage-resistant, propeller-driven toy

ABSTRACT

An impact-damage-resistant nose construction for use with propeller driven flying toy aircraft, the nose construction including an energy absorber connected to the fuselage and including a portion which is positioned between the propeller and the power plant with a movable coupling connecting a propeller shaft to the power plant so that the propeller may move axially relative to the power plant when the energy absorber is deformed by an impact.

{mite States Patent Chang et a1.

[ 1 Sept. 11, 1973 1 1 lMPACT-DAMAGE-RESISTANT,

PROPELLER-DRIVEN TOY [75] lnventors: Richard S. Chang, Rolling HillsEstates; William A. Staats, Torrance; Denis V. Bosley, Palos VerdesPeninsula", Toshio Yamasaki, Gardena, all of Calif.

[73] Assignee: Mattel, Inc., Hawthorne, Calif.

[22] Filed: Aug. 7, 1972 [21] Appl. No.: 278,507

[52] U.S. Cl 46/243 AV, 46/78 [51] Int. Cl. A63h 27/00, A63h 33/26 [58]Field of Search 46/76, 78, 81, 243 AV; 244/1 [56] I References CitedUNITED STATES PATENTS 3,232,564 2/1966 Benson 46/78 PrimaryExaminerLouis G. Mancene Assistant ExaminerR0bert F. CuttingAtt0rneySeymour A. Scholnick [57] ABSTRACT An impact-damage-resistantnose construction for use with propeller driven flying toy aircraft, thenose construction including an energy absorber connected to the fuselageand including a portion which is positionedbetween the propeller and thepower plant with a mov-.

able coupling connecting a propeller shaft to the power plant so thatthe propeller may move axially relative to the power plant when theenergy absorber is deformed by an impact.

20 Claims, 12 Drawing Figures PATENTED SEP I I973 SHEET 1 BF 5PATENTEDSEPI i ma sum 2 0F 5 sum 3 (IF 5 PATENTED SEP] 1 I975IMPACT-DAMAGE-RESISTANT, PROPELLER-DRIVEN TOY BACKGROUND OF THEINVENTION The background of the invention will be set forth in twoparts.

FIELD OF THE INVENTION The present invention pertains generally to thefield of toys and more particularly to impact-damageresistant,propeller-driven toys subject to impact with the ground and otherobjects.

DESCRIPTION OF THE PRIOR ART The probability that flyable toy aircraftwill sooner or later impact the ground or structures situated thereonand be severely damaged, is well established. In nearly all suchinstances, the impact is incident on the front end of the craft. Theforce may damage the propeller, and the toys air frame and power planthoused therein.

SUMMARY OF THE INVENTION In view of the foregoing factors and conditionscharacteristic of the prior art, it is a primary object of the presentinvention to provide a new and improved impact-damage-resistant,propeller-driven toy.

Another object of the present invention is to provide a relativelylightweight, resiliently-deformable, impactdamage-resistant flyable toyaircraft.

Still snother object of the present invention is to provide animpact-damage-resistant, propeller-driven toy that includes structurerotationally coupling the toys power plant to its propeller whileallowing relative movement therebetween.

It is still another object of the present invention to provide a noseconstruction for motor-powered, propeller-driven toys that allows thepropeller shaft to move both inwardly and laterally upon severe impactwithout damaging the shaft or the drive mechanism which rotates theshaft and propeller.

According to the present invention, two embodiments of animpact-damage-resistant nose construction are provided for use withmotor-powered and propeller-driven toys, such as toy aircraft. Oneembodiment includes a propeller shaft housing having a circularcross-sectioned hollow elongated nose portion with a propeller-facingforwardend. The housing also includes a circular-cross-sectioned,increased-diameter, hollow rear portion, the elongated nose portion andthe rear portion being joined by a hollow, integral, truncated coneportion exhibiting a variable resistance to compressive load. Thetruncated cone portion slopes forward from its larger-diameter edge, andit, along with the rear and nose portions are axially aligned with acommon longitudinal axis, namely the rotational axis of the propellershaft contained therein. Preferably, the elongated nose portion is ahollow truncated cone with its smaller end located at the forward partof the housing, the outer surface of this elongated nose portionpreferably including a plurality of uniformly spaced longitudinal ribs.

In a second and third embodiment of the present invention, a fuselageframe has a forward end and a rear end. A power plant is mounted in theframe, and energy absorbing means is connected to the frame at theforward end of the fuselage frame for absorbing impact energy incidentat the front of the fuselage. Also ineluded is power transmitting meansoperatively coupled to the propeller and to the power plant through theenergy absorbing means for transmitting rotational power from the powerplant to the propeller and allowing relative movement therebetwen.

The power transmitting means may include a coupling structure havingoppositely disposed shaft coupling portions, the portions coaxiallyoverlapping to allow relative axial movement therebetween, but beingkeyed to maintain rotational integrity.

The features of the present invention which are believed to be novel areset forth with particularity in the appended claims. The presentinvention, both as to its organization and manner of operation, togetherwith further objects and advantages thereof, may best be understood bymaking reference to the following description, taken in conjunction withthe accompanying drawings in which like reference characters refer tolike components in the several views.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view,partially in section, illustrating a first embodiment of the inventivestructure and a flying toy aircraft carrying same;

FIG. 2 is a perspective view showing, in enlarged form, the forwardportion of the toy aircraft of FIG. 1;

FIG. 3 is an enlarged sectional view of the nose portion of the aircraftstructure taken along line 3-3 of FIG. 1;

FIG. 4 illustrates the reaction of the propeller housing structure ofFIG. 1 to initial impact forces on the propeller;

FIG. 5 illustrates how the propeller housing absorbs the impact forceswithout allowing the propeller shaft and the power train coupled theretoto be damaged;

FIG. 6is an elevational view of a modified propeller shaft housingstructure;

FIG. 7 is an end view of the propeller shaft housing structure of FIG.6;

FIG. 8 is an elevational view, partially broken away, of the forwardportion of a flyable toy aircraft constructed in accordance with asecond embodiment of the present invention;

FIG. 9 is a plan view of that aircraft illustrated in FIG. 8;

FIG. 10 is a plan view of the toy, similar to that seen in FIG. 9, butillustrating the change in relative positions of the crafts componentsupon impact;

FIG. 11 is a partially broken away elevational view of the front endportion of a flyable toy aircraft constructed in accordance with a thirdembodiment of the present invention; and

FIG. 12 illustrates impact-caused deformation of the forward portion ofthe toy seen in FIG. 11 as would be caused by the toys impact with theground, for example.

portion of the flyable toy DESCRIPTION OF THE INVENTION Referring againto the drawings, and more particu larly to FIG. 1, there is shown apropeller-driven toy, such as a flyable toy aircraft 11 havingconventional wings 13, a body or fuselage 15, a cowling l7, and apropeller 19. The fuselage may be provided with simulated windows 21 anda windshield 23 and other simulated fixtures and appendages such as alanding gear, not here shown for the sake of simplicity.

Referring now also to FIG. 2, it can be seen that a forward housing ornose cone portion 25 is detachable from the remainder of the crafts bodyor fuselage 15. The portion 25 has a forward end 27 and an attachmentportion 29, the latter including attachment means (described in moredetail later) for removably attaching the portion 25 to the toy aircraft11. The attachment portion basically comprises a transverse plate orwall 31 that lies in a plane orthogonal to the longitudinal axis 33 of apropeller shaft 35 rotatably disposed in the portion 25 and extendingbeyond the forward end 27 and seated at its threaded end 36 in athreaded bore 37 in the propeller 19. In this embodiment, the wall 31 isgenerally rectangular and has a lower indexing portion 41 registeringwith lower holding brackets 43 which are an integral part of anattachmentbulkhead or frame 45 fixedly attached to a forward portion ofthe fuselage 15 (note arrows 47 in FIG. 2).

The bulkhead 45 has an outer edge 49 which conforms to the cross sectionof the fuselage 15 and a generally rectangular central opening 51. Theframe 45 also includes forwardly extending positioning members 53 and aresilient holding tab 55 with an inwardly extending lip portion 57. Thetab 55 and the members 53 are preferably an integral part of the singleplastic molded bulkhead 45, which frame may be either an integrallymolded part of the aircraft fuselage or permanently attached thereto byconventional bonding means such as a plastic cement, for example. In thelatter case, frame 45 will include a flange portion 59 which slidablyfits within the fuselage l and bonded thereat. Slots 63 are provided inthe fuselage to accommodate a pair of rubber band tie down members 65,the rubber bands (not shown) being used to hold the wing 13 in place.

From'FIG. 2, it can be seen that the portion 25 is removably attached tothe fuselage by first inserting the indexing portion 41 into the holdingbrackets 43 and the upper edge 67 of the plate 31 is then moved intocontact with the holding tab 55, as indicated by arrows 69. Additionalrearward pressure on the plate 31 or the lifting of the tab 55'willallowthe lip portion 57 to slide over the edge 67 and then down to holdthe plate against the positioning members 53. These members 53 may besloped and dimensioned to position the longitudinal axis 33 of thepropeller shaft 35 relative to the longitudinal axis 70 of the fuselagefor certain desired effects such as counteracting the propeller torquefor straight powered flight, with the control surfaces (not shown) intheir neutral position, for example. This technique is well-known in theart and will not be described here in detail.

Extending rearwardly from the wall 31 are a pair of spaced parallelbroadly flat arms 71 which terminate at a forward wall 73 of arectangular open frame 75. The inner face 77 of the plate 31 and theforward face 79 of the wall 73 carry cylindrical lip portions 81 adaptedto fit about and fixedly hold in place a powerful miniature electricmotor 83, best seen in FIG. 1. Extending in back of a rear wall 85 ofthe frame 75 is a somewhat smaller battery-compartment, open-framearrangement 87 which securely holds, in this embodiment, a pair oftandemly mounted, electrically series connected, rechargeablenickel-cadmium batteries 89, 91. This battery of cells 89 and 91 may beconsidered as a single battery arrangement 93 with a positive batteryterminal 95 and a negative battery terminal 97 (the outer case of thelower cell 91).

A positive contact member 99 of a metal conductive material such asbrass, for example, is bent to extend between and is permanentlyattached and electrically connected to one input terminal 100 of themotor 83 and to the positive battery terminal 95 of the batteryarrangement 93. The member 99 also extends beyond the batterycompartment 87 and finally terminates at a V-shaped positive chargingplug tip contact 101 seated on supporting edges 103 of a recharging plugenclosure member 105 mounted at the rear wall 107 of the frame 87. Alower wall 109 of the frame 87 is in the form of a hollow conduit havinga rectangular cross section which slideably houses an elongated switchmember 111 with a switch operating depending tab 113. The member 111includes a travel limit projection 115 moving in an elongated slot 117in a lower wall portion 119 of the wall 109. A plug accepting hole 121is also provided in the member 111 which hole registers with arecharging plug passageway 123, defined by the enclosure member 105,only when the member 111 is in its off position (extreme forwardposition).

The switch member 111 is also provided with an upwardly extending tab125 adjacent the forward end thereof. The tab 125 pushes a negativebattery contact end 127 of a conductive negative contact member 129 intophysical and electrical contact with the negative battery terminal 97against the self-biasing resiliency of the member 129, only when the tab113 is pushed in a rearward direction to its extreme rear or on"position, as indicated by arrow 13]. Since the negative contact member129 is permanently connected to a second motor input terminal 133, theelectrical supply circuit to the motor 83 is complete when the contactend 122 is forced to touch the negative battery terminal 97, and themotor is thus activated.

In order the charge the battery arrangement 93, a conventional chargingplug (not shown) having a tubular sleeve and an insulated tip isinserted through the hole 129 into the passage 123 until the plugs tip(positive polarity) contacts and registers with the tip contact 101, andthe plugs sleeve (negative polarity) lies against and makes electricalcontact with the negative battery terminal 97, which is the outer caseof the cell 91. Once the battery arrangement has been charged, thecharging plug may be removed and the tab 113 pushed rearward to energizethe motor 83.

As can be seen in FIG. 1, the electric motor 83 includes a motor shaft141 extending through an appropriate opening in the plate 31 andsupporting a relatively small diameter pinion 143. Supported by arotatable axle 145 rotatably extending through a bearin g aperture 147in the plate 31, is a relatively larger diameter coupling gear 149having teeth 150 disposed about its outer circumference meshed with thepinion 143. As shown more cleariy in the enlarged view of FIG. 3, thecoupling gear 149 includes an axial spacer projection 151 with anelongated axial bore 153 wherein the axle 145 is fixedly attached. Thegear 149 may be fabricated from any suitable substance such as a nylonmaterial, for example, and the projection 151 may be an integral part ofthe gear 149, which projection maintains a minimum distance between thegears and the plate 31.

The gear 149 is further provided with holes 155 symmetrically spacedabout the axis 35 to accommodate and hold a similar number ofprojections 157 of a hollow, truncated, conically-shaped, resilientcoupling member 159 (alternately the member 159 may be bonded directlyto the gear 149). The projections 157 extend from the base periphery 161of the hollow truncated conically-shaped member 159 and includerelatively larger diameter retaining end portions 163 in order to holdthe member 159 in position against the gear 149. The coupling member 159is designated to be compressible axially (see FIGS. 4 and 5) anddistorted laterally but still be able to effectively transmit torquebetween its base periphery 161 and its forward tubular axial projection165. It has been found that a rubber or neoprene material is suitablefor this application, but other materials exhibiting the desiredcharacteristics may be used. This coupler also allows easy disassemblyby simply pulling propeller and shaft out. Shaft 35 is then taken out ofpropeller 19 for reassembly.

An axial bore 169 is provided in the projection 165 with an innerdiameter less than the diameter of the shaft 35 so that a significantfrictional grip is provided by the coupling member on the propellershaft to transmit torque thereto. The shaft 35 is rotatably supported atthe housing's forward end 27 by a bearing element 171 with an axial bore173 and which has an axially aligned bushing portion 175 and an annulardisc portion 177. The bushing portion 175 has an outer diameter toslideably fit within a bore 179 in the housing 25 adjacent the front end27 to support the shaft 35 thereat. The annular disc portion 177 is atleast the spinner diameter of the propeller 19 so that the impact forceis transmitted over the full area of the material.

In the embodiment illustrated in FIGS. l-S, the portion 25 includes aremovable propeller shaft housing structure 181 having a relativelylarge diameter hollow cylindrical rear portion 183 terminate at a rearperipheral edge 185 against the plate 31, and an elongated tubularportion 187 with a ribbed, reduced-diameter forward portion 189terminated at the end 27.

Integrally joining the rear portion 183 to the elongated tubular portion187 is a unique hollow truncated cone portion 191 exhibiting anapproximately constant force characteristic with compressibledisplacement. The exact nature of this force characteristic associatedwith a given compressible displacement is determined by the materialused, the thickness of the'material in the truncated region, the smaller193 and the larger 195 diameters of this conical structure and the coneangle. The purpose of this configuration is to provide an advantageousshock absorbing feature as an integral part of the housing structure 25.The portion 191 is in effect similar to a dish-shaped disc spring knownin the mechanical art as a Belleville spring, although it is modified byits integral attachment to the cylindrical portions. Additionalinformation concerning this type of device may be obtained by makingreference to texts such as Fundamentals of Machine Design" by C. A.Normal et al., published by the MacMillan Company, New York.

The design of the portion 25 is thus directed to the preventing orlessening of damage to the power train and airframe structures andcomponents, in the event of a severe compressive load inwardly exertedon the nose of the aircraft 11, as when the latter crashes nose first tothe ground or into a wall; an event which may occur when inexperiencedpersons control the craft or when natural forces of sufficient magnitudeovercome the natural stability of the craft in flight.

Referring now more particularly to FIGS. 4 and 5 the operation of thevarious structures and elements of the nose portion of the aircraft 11to resist impact damage is illustrated. Upon initial contact with theground, for example, the propeller l9 and its attached shaft 35 will bepushed rearwardly causing some deformation in the resilient couplingmember 159, as illustrated in FIG. 4. It can be seen that the member 159is disposed between the inwardly moving shaft 35 and the gear 149 whichcannot so move because of its spacer portion 151 being in contact withthe plate 31. The conical side walls of this member will thus buckle andabsorb energy without transmitting excessive forces to the gear 149 orthe plate 31. The resiliency of the coupling member 159 also allows therear end of the propeller shaft 35 to move laterally without deformingthe shaft when the impact force exerted on the propeller 19 includescomponents in directions other than along the rotational axis 33 of theshaft 35.

In the event that the force is greater than that which can be absorbedby the action of the coupling member 159, the propeller will be pushedagainst the disc por tion 177 of the bearing member 171, which will inturn push against the end 27 of the nose cone portion 25. This forcewill then be transmitted back along the rigid elongated tubular portion187 of the truncated cone portion 191 which is fixedly anchored at itsouter periphery 195 by the rigid hollow cylindrical portion 183 and theplate 31. This compressive load will cause the more inward region of theconical portion 191 to deflect relatively towards the plate 31, at firstat a relatively fast pace, but at a non-linear, increasingly lesserrate. The deflection of the member 191 is shown in FIG. 5 by comparingits original position (identified by the dashed outline 191') and itsfinal position shown by the solid outline 191". By taking intoconsideration the mass of the aircraft l1 and the possible maximumvelocity with which it may impact the ground or another object, oneskilled in the art will be able to design a shock absorbing portion 191which will absorb the compressive energy so produced and prevent severedamage to the craft, particularly the motor, battery of cells and geartrain, from excessive deceleration forces.

In order to facilitate assembly and removal of the propeller shafthousing 181, a rotating-lock attachment arrangement is provided on theplate 31 and at the peripheral edge of the housing's rear portion 183,as best illustrated in FIG. 2. This arrangement includes three specedL-shapedretaining brackets.201 on the forward face 203 of the plate 31and three associated tabs 205 extending radially from the edge 185. Toassemble these units, the tabs 205 are positioned against the platesfront face 203, at one side of the brackets 201, before rotating thehousing 101 and thereby moving the tabs 205 into engagement with thebrackets. Also, the front face 203 of the plate may include circularsegment ridges 207 which register with the inner surface 209 of theportion 183 for proper axial alignment, thereof. Additionally, a stopprojection 211 may be provided adjacent one side of one of the tabs 205to restrict the amount of such rotation so that the tabs will becentered in the holding brackets, as shown more clearly in theembodiment of FIGS. 6 and 7.

Another embodiment of the propeller shaft housing structure 181 is shownin FIGS. 6 and 7 and designated cone configuration 187' is substitutedfor the tubular structure 187 and the ribbed reduced diameter portion189. Elongated ribs 213 radiate gradually as they extend back from thefront end 27 to provide additional compressive rigidity and strength tothe elongated portion 187.

Referring now to FIGS. 8 and 9, there is shown a second embodiment of aflyable toy aircraft 311 having a fuselage 313, a wing member 315mounted on the fuselage 313, and a propeller 317 rotatably mounted bymeans of a propeller shaft 319 at the nose portion 321 of the fuselage313. Mounted in the fuselage 313 is a power plant 323 including anelectric motor 325, the output shaft 327 of which carries a pinion gear329 meshed with and driving an output gear 331 mounted on an outputshaft 333 of the gear train assembly 335. The electric motor 325 ispreferably mounted directly on the gear train assemblys frame 337 whichin turn is bolted or otherwise attached to a bulkhead member 339 withinthe fuselage structure or frame 313.

In this embodiment of the invention, the forward portion 321 of theaircrafts fuselage 313 includes a cuplike nose structure 341 slidablymounted over a fuselage cowling portion 343. Within the fuselagesforward portion 321, a generally U-shaped energy absorbing member 345 isattached at its ends 347, by any suitable means such as rivets 349, tobrackets 351 extending in generally a forward direction from, and asintegral parts of, the bulkhead structure 339.

As can be seen in FIGS. 8 and 9, the resilient energy absorbing member345 has relatively broad surfaced sides 353 and a generally transversefront end portion 355 wherein a; hole 357 is located. The hole 357 isaligned with'a hole 359 in the nose structure 341 in order to accept abushing oprtion 361 inwardly extending from, and an integral part of, athrust bearing disc portion 363 lying in a plane orthogonal to therotational axis 365 of the propeller shaft 319. As can best be seen inFIG. '8, the propeller shaft 319 is rotatably supported in an elongatedbore 366 extending through the portions 361 and 363 comprising a frontbearing member 367.

The output shaft 333 of the gear train assembly 335 is operativelycoupled to the rear end 371 of the propellershaft 319 through a-movablecoupling means comprising a special coupling assembly 373 which includesan elongated member 375 having an axial bore 377 dimensioned to forciblyaccept, or by any other means attached to, an outer end 379 of theoutput shaft 333. Also, the opposite end of the member 375 is providedwith a bore 381 having an axis aligned with that of the bore 377, anddimensioned to slidably accept the end 371 of the propeller shaft 319.An elongated slot 383 is milled or otherwise provided in the side 385 ofthe member 375 and communicates with the bore 377. Preferably, the slot383 extends completely through the member 375 to accept a pair of arms387 transversely extending from the shaft end portion 371. In thismanner, the end portion 371 may slide axially in the bore 377, onlylimited by the length of the slot 383, while any rotationalmovement ofthe output shaft 333 is transmitted through the member 375 to the arms387 and thus to the shaft 319 and its fixedly attached propeller 317.

In normal operation, the motor 325 is activated by conventional meansand the rotational power of its shaft 327 is transferred through thereduction gear train assembly 335 to the output shaft 333 and throughthe special coupling assembly 373 to the shaft 319 and the propeller317. The length of the shaft 319 is such that the arms 387 are normallypositioned adjacent the forward end of the slot 383, as shown in FIGS. 8and 9.

Impact force incident on the toy will usually occur at the propeller'sspinner area 389 to cause a rearward movement thereof. This isillustrated in FIG. 10 by the position of the spinner 389 and the nosestructure 341, as compared to the normal position of the spinner andstructure 341 indicated by the dashed outlines 391 and 393,respectively. This movement of the spinner 389 causes it to force thebearing member 367 to push against the nose structure 341, which inturn, transfers the force to the transverse end 355 of the resilientenergy absorbing member 345. The inward force impressed on the end 355causes the energy absorbing members sides 353 to bow outwardly andthereby dissipate much of the impact energy.

As may be seen in FIG. 10, the inward movement of the spinner 389 causesno harm to the nose structure 341 or to the fuselage cowling portion 343since the sidewall 395 of the nose structure 341 slides over the outersurface 397 of the fuselage cowling portion 343. Also, the chance ofdamage to the propeller shaft 319 and to the gear train assembly 335 andits driving motor 325, is significantly minimized, upon impact, becausethe special coupling assembly 373 allows the end por tion 371 of thepropeller shaft 319 to freely move inwardly the length of the slot 383,as seen in FIG. 10.

A third embodiment of the present invention is illustrated in FIGS. 11and 12. Here, there is shown the front portion of a flyable toy aircraft401 constructed similarly to the previously described toy 311, exceptfor the energy absorbing structure. In this embodiment, the energyabsorbing member 353 and the nose structure 341 are replaced by a moldedresilient energy absorbing nose member 402 having an opening 405 in aforward end 407 thereof. The axial bushing portion 361 of the frontbearing member 367 extends through the opening 405 so that the propellershafts rotational axis 365 is aligned with the rotational axis of thespecial coupling assembly 373 and the output shaft 333. An edge portion409 of the nose member 403 registers in and is preferably bonded to anoffset lip portion 41 1 at the leading edge of the fuselage cowlingportion 343A.

FIG. 12 illustrates that upon impact, the propellers spinner area 389forces the front bearing member 367 against the forward end 407 of theenergy absorbing nose member 403. This action causes the nose member 402to deform in a manner that substantially absorbs the impact energy andprevents it from being directly transferred to the fuselage of theaircraft 401. As in the case of the previously described embodiments ofthe invention, the inward movement of the propeller shaft 319 is nottransferred to the output shaft 333 of the gear train assembly 335 dueto the design of the special coupling assembly 373. Additionally, aspring 382 may be provided in bore 381 to absorb energy by beingcompressed when arms 387 move from the position shown in FIG. 11 to theposition shown in FIG. 12. Lateral displacement of shaft 319 may beaccommodated by providing a ball 333A on output shaft 333 and bydrivingly connecting ball 333A to coupling assembly 373 with a pin 333Bpassing through ball 333A and engaging a bifurcated end 333c on couplingassembly 373.

From the foregoing, it should be evident that the present inventionprovides a propeller-driven toy structure that resists impact damage andconstitutes a significant advancement of the propeller-driven toy art.

It should be understood that the materials used in fabricating thevarious components of the aircraft structure described above are notcritical and any material generally considered suitable for a particularfunction may be utilized.

Although three embodiments of the invention have been described indetail, it should be understood that other embodiments and modificationsof the invention may be constructed in accordance with the teachings ofthe invention as described herein. Accordingly, it is intended that theforegoing disclosure and drawings shall be considered only asillustrations of the principles of this invention.

What is claimed is:

1. In a propeller-driven toy having a body, a propeller, a power plantand power transmitting means operatively coupling said propeller to saidpower plant at one end of said body, improved meansfor resisting impactdamage, comprising:

energy absorbing means mounted in said toy between said propeller andsaid power plant for absorbing impact energy incident to said one end ofsaid body; and

movable coupling means provided on said power transmitting means foroperatively coupling said propeller to said power plant through saidenergy absorbing means, whereby said propeller may move axially relativeto said power plant when said energy absorbing means is deformed by animpact.

2. The improvement according to claim 1 wherein said energy absorbingmeans is a resilient member forming part of said movable coupling means.

3. The improvement according to claim 2 wherein said movable couplingmeans is an elongated member having an axial bore slidably receiving apropeller shaft connected to said propeller and wherein said resilientmember is a spring mounted in said axial bore for receiving compressiveforces from said propeller shaft.

4. The improvement according to claim 2 wherein said power transmittingmeans includes a propeller shaft having one end connected to saidpropeller and wherein said resilient member is a hollow, truncated,conically-shaped member connecting the other end of said propeller shaftto said power plant.

5. The improvement according to claim 1 wherein said energy absorbingmeans includes:

a propeller-shaft housing structure having an elongated nose portionwith a propeller-facing end, and

having an increased-diameter portion, said elongated nose portion andsaid increased-diameter portion being joined by an integral truncatedcone portion exhibiting an approximately constant force characteristicwith compression displacement, said nose portion, increased-diameterportion and truncated cone portion being axially aligned with a commonlongitudinal axis.

6. The improvement according to claim 5, wherein said elongated noseportion is a hollow truncated cone.

7. The improvement according to claim 5, wherein at least the forwardportion of the outer surface of said elongated nose portion includes aplurality of uniformly spaced longitudinal ribs.

8. The improvement according to claim 5, wherein said elongated noseportion includes an elongated tube portion and a reduced-diameter tubeportion terminating at said propeller-facing end.

9. The improvement according to claim 5, wherein said power transmittingmeans includes an elongated propeller shaft rotatably disposed in saidhousing structure essentially along said longitudinal axis and extendingbeyond said propeller-facing end, and a shaftdriving gear rotatablymounted in said housing structure perpendicular to and centered alongsaid longitudinal axis, and wherein said movable coupling means includesa resilient coupling member attached between one end of said propellershaft and said shaft-driving gear allowing a restrained degree of axialand lateral displacement of said propeller shaft at the juncture of saidpropeller shaft and said coupling member.

10. The improvement according to claim 9, wherein said shaft-drivinggear includes a plurality of apertures symmetrically spaced about saidlongitudinal axis, and wherein said resilient coupling member includes ashaft-accepting bore and a plurality of rearwardlyextending projectionsregistering with and captured by said plurality'of apertures in saidshaft-driving gear.

11. The improvement according to claim 10, wherein said resilientcoupling-member includes a tubular forward portion having ashaft-accepting bore for receiving one end of said propeller shaft andrelatively thinwalled, hollow, truncated-cone rear portion, saidprojections extending from the base edge of said truncated-cone rearportion.

12. The improvement according to claim 9, wherein said propeller isprovided with an axial bore and wherein said power transmitting meansincludes a nose bearing member having an axial bushing portion and atransverse annular washer portion integral therewith,

the other end of said propeller shaft being seated in said axial bore ofsaid propeller, said axial bushing portion of said nosebearing memberbeing disposed in the axial opening in said propeller-facing end of said'nose portion, and said annular transverse washer portion being disposedbetween said propeller and said propellerfacing end of said noseportion.

13. The improvement according to claim 1, wherein said powertransmitting means includes a power output shaft on said power plant andan elongated propeller shaft attached at a forward end to saidpropeller, said propeller shaft lying essentially in line with the axisof rotation of said power output shaft, said movable coupling meansbeing fixedly attached to and between a rear end of said propeller shaftand said power output shaft for rotating said propeller shaft withrotation of said 'power output shaft while allowing relative axialmovement between said shafts.

14. The improvement according to claim 13, wherein said movable couplingmeans includes an elongated member having an elongated bore thereindimensioned to slidably accept one of said shafts therein, saidelongated member also including a second bore axially aligned with saidelongated bore and in which the other of said shafts is fixedly held,said elongated member further including at least one elongated slot inits outer surface communicating and axially aligned with said elongatedbore, said movable coupling means also including guide means fixedlyassociated with one of said rubber material.

18. The improvement according to claim 15, wherein said resilient memberis a generally U-shaped band of metal attached at its end at oppositesides of said body.

19. The improvement according to claim I8, wherein said body is anairplane fuselage and wherein said band lies within the cowling portionof the said fuselage.

20. The improvement according to claim 19, wherein said cowling includesan inwardly slidable nose portion overlapping a fuselage portion.

a: a a k

1. In a propeller-driven toy having a body, a propeller, a power plantand power transmitting means operatively coupling said propeller to saidpower plant at one end of said body, improved means for resisting impactdamage, comprising: energy absorbing means mounted in said toy betweensaid propeller and said power plant for absorbing impact energy incidentto said one end of said body; and movable coupling means provided onsaid power transmitting means for operatively coupling said propeller tosaid power plant through said energy absorbing means, whereby saidpropeller may move axially relative to said power plant when said energyabsorbing means is deformed by an impact.
 2. The improvement accordingto claim 1 wherein said energy absorbing means is a resilient memberforming part of said movable coupling means.
 3. The improvementaccording to claim 2 wherein said movable coupling means is an elongatedmember having an axial bore slidably receiving a propeller shaftconnected to said propeller and wherein said resilient member is aspring mounted in said axial bore for receiving compressive forces fromsaid propeller shaft.
 4. The improvement according to claim 2 whereinsaid power transmitting means includes a propeller shaft having one endconnected to said propeller and wherein said resilient member is ahollow, truncated, conically-shaped member connecting the other end ofsaid propeller shaft to said power plant.
 5. The improvement accordingto claim 1 wherein said energy absorbing means includes: apropeller-shaft housing structure having an elongated nose portion witha propeller-facing end, and having an increased-diameter portion, saidelongated nose portion and said increased-diameter portion being joinedby an integral truncated cone portion exhibiting an approximatelyconstant force characteristic with compression displacement, said noseportion, increased-diameter portion and truncated cone portion beingaxially aligned with a common longitudinal axis.
 6. The improvementaccording to claim 5, wherein said elongated nose portion is a hollowtruncated cone.
 7. The improvement according to claim 5, wherein atleast the forward portion of the outer surface of said elongated noseportion includes a plurality of uniformly spaced longitudinal ribs. 8.The improvement according to claim 5, wherein said elongated noseportion includes an elongated tube portion and a reduced-diameter tubeportion terminating at saId propeller-facing end.
 9. The improvementaccording to claim 5, wherein said power transmitting means includes anelongated propeller shaft rotatably disposed in said housing structureessentially along said longitudinal axis and extending beyond saidpropeller-facing end, and a shaft-driving gear rotatably mounted in saidhousing structure perpendicular to and centered along said longitudinalaxis, and wherein said movable coupling means includes a resilientcoupling member attached between one end of said propeller shaft andsaid shaft-driving gear allowing a restrained degree of axial andlateral displacement of said propeller shaft at the juncture of saidpropeller shaft and said coupling member.
 10. The improvement accordingto claim 9, wherein said shaft-driving gear includes a plurality ofapertures symmetrically spaced about said longitudinal axis, and whereinsaid resilient coupling member includes a shaft-accepting bore and aplurality of rearwardly-extending projections registering with andcaptured by said plurality of apertures in said shaft-driving gear. 11.The improvement according to claim 10, wherein said resilient couplingmember includes a tubular forward portion having a shaft-accepting borefor receiving one end of said propeller shaft and relativelythin-walled, hollow, truncated-cone rear portion, said projectionsextending from the base edge of said truncated-cone rear portion. 12.The improvement according to claim 9, wherein said propeller is providedwith an axial bore and wherein said power transmitting means includes anose bearing member having an axial bushing portion and a transverseannular washer portion integral therewith, the other end of saidpropeller shaft being seated in said axial bore of said propeller, saidaxial bushing portion of said nose bearing member being disposed in theaxial opening in said propeller-facing end of said nose portion, andsaid annular transverse washer portion being disposed between saidpropeller and said propeller-facing end of said nose portion.
 13. Theimprovement according to claim 1, wherein said power transmitting meansincludes a power output shaft on said power plant and an elongatedpropeller shaft attached at a forward end to said propeller, saidpropeller shaft lying essentially in line with the axis of rotation ofsaid power output shaft, said movable coupling means being fixedlyattached to and between a rear end of said propeller shaft and saidpower output shaft for rotating said propeller shaft with rotation ofsaid power output shaft while allowing relative axial movement betweensaid shafts.
 14. The improvement according to claim 13, wherein saidmovable coupling means includes an elongated member having an elongatedbore therein dimensioned to slidably accept one of said shafts therein,said elongated member also including a second bore axially aligned withsaid elongated bore and in which the other of said shafts is fixedlyheld, said elongated member further including at least one elongatedslot in its outer surface communicating and axially aligned with saidelongated bore, said movable coupling means also including guide meansfixedly associated with one of said shafts and slidably positioned andcaptured in said elongated slot.
 15. The improvement according to claim1, wherein said energy absorbing means includes a resilient memberattached to said body, a portion of said resilient member lyingimmediately behind said propeller.
 16. The improvement according toclaim 15, wherein said resilient member forms a portion of the cowlingat the front of said body.
 17. The improvement according to claim 15,wherein said resilient member is fabricated from a synthetic rubbermaterial.
 18. The improvement according to claim 15, wherein saidresilient member is a generally U-shaped band of metal attached at itsend at opposite sides of said body.
 19. The improvement according toclaim 18, wherein said body is an airplane fuselage and wherein saidband lies wIthin the cowling portion of the said fuselage.
 20. Theimprovement according to claim 19, wherein said cowling includes aninwardly slidable nose portion overlapping a fuselage portion.